Combustion chambers and injection systems for direct fuel injection in two stroke diesel engines are for example disclosed in Jikaisho No. 62-57733 and Tokkaihei No. 1-315631 published by the Japanese Patent Office.
In these engines, fuel is injected into the combustion chamber in the latter half of the compression step. This prevents the injection fuel from being blown out from the exhaust valve. However, due to this setting, insufficient conversion of fuel to fine particles and poor dispersion are apt to occur and fuel tends to mix poorly with air. This leads to poor fuel consumption performance and reduced power, and an undesirable composition of exhaust gases.